Apparatus for bleaching and aging flour and other grain products.



No. 382,526. PATENTBD MAR. 17, 190s'.

P. MBARS A; J. CRAIG. APPARATUS POR BLEACHING AND AGING FLOUR AND OTHERGRAAN PRODUGTS. APPLoATIoN NLM) Anny/,1907.

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UNITED i STATES PATENT OFFIQE.

FRED MEARS, OF MINNEAPOLIS, AND JOSEPH CRAIG, Ol" PRIN(.`ETON, MINNESOTA, ASSIGN- ORS, BY DIRECT AND MESNE ASSIGNMENTS, TO HYGIENIO REFINElt ('IOMIAY, OF PRINCETON, MINNESOTA, A CORPORATION OF MINNESOTA.

APPARATUS FOR BLEACHING AND AGING FLOUR AND OTHER GRAIN PRODUCTS.

Specification of Letters Patent.

Patented March 17, 1908.

Application filed Aprile?, 1907. serial No. 370,719.

T o all whom it may concern:

Be it known that we, FRED MEARS and JosEPH CRAIG, 'citizens of the United States, residing at Minneapolis and Princeton, in the counties of Hennepin and Millelacs and State of Minnesota, have invented certain new and useful Improvements in Apparatus for Bleaching and\'Aging Flour and other Grain Products; and we do hereby declare the foli lowing to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use thesame.

Our invention has for its object to provide an efficient apparatus for bleaching and aging flour and other grain products; and, to this end, our invention consists of the novel devices and combinations of devices hereinafter described and pointed out in the claims.

The ap aratus is illustrated in the accompanying diawings, wherein like notations indicate like parts throughout the several views.

Referring to the drawings; Figure 1 is a View chiefly in side elevation, but partly in vertical section, with someportions broken away, illustrating our im roved ap aratus. Fig. 2 is a plan view of t e parts s own in Fig. 1, with some portions removed and lothers shown in diagram lines only. Fig. 3 is a detail showing the flour distributing head deltached, in plan view; and Fig. 4 is a detail showing the gas generator detached, chiefly in vertical section but with some parts lin elevation.

Upon a suitable skeleton frame 1 is mounted a pair of cylindrical mixing vessels 2, closed at their upper ends and having hopper-like bottoms. f In each ofrt'hese vessels 2 1s suitably supported a rotary shaft 3, having at its upper end a beveled pinion 4 engaging 'a bevel gear 5 on countershaft 6. Each countershaft 6 is shown as provided with a sprocket wheel 7 connected by a chain 8 with a main shaft 9 receiving motion from any suitable source, not shown.

As shown, the shaft 3 is supported by a bearing bracket 10 fixed to the walls of the' -mixing Vessel 2, and an lpper bracket l1 projecting from a standar 12 rising from the main frame 1, and v'which also suplports owerl the bearings for the shaft 6. To the end of the shaft 3 -is fixed a screw blade 13 coperating with the shaft 3 to afford a screw conveyer working in the neck or outlet of the hopper-like bottom of the mixing vessel 2. To the shaft 3, within the vessel 2, at a suitable point below the head or upper end of the vess'el 2, is located a flour distributing head 14 which, as shown, is of approximately disk-like form', its' central portion being a solid web and its outer' portion being made up of radial projections or fingers extending outward from the solid web, and bent upon themselves so as to assume somewhat the shapeof propeller blades or paddle arms, as can be readily understood from an ins ection of Figs. 1 and-3.- The flour is supp ied from an^ overhead'source through the main trunk or chute 15, having a pair of divergin legs 16, the feet sectionsv of which are vertica and of cylindrical rform, and tap or are secured to the heads of the vessels 2. At the point where the legs 16 'diverge from the trunk'15, is located a weighted 'valve 17 which may be shifted to throw the flour to either of the vessels 2 and shut the same off from the other, whenever so desired. In the vertical or feet sections of the legs 16 is mounted a flanged sleeve 18 in such a Way that it will telescope or move freely up and down therein. The sleeve 18 is adjustably supported by a hand screw 19 ta ped through-the head 'ofthe vessel 2 and talking holdof the sleeve'flange.` The shaft 3 passes out through Ithe sleeve 18 and ftheve'rtical section of the flour' supply leg 16. "By adjusting the` sleeve 18 up or down, it may be brought nearer to or farther away from the distributing head 14, and thus be made to regulate the flour or feed supply to the mixing chamber 2.

On the top of the frame 1 is mounted a suitable casing 2() adapted to sulport the working parts of the gas enerator. As shown, the casing 20 is provi ed with a door 20, and a false ybottom 2l mounted on hand screw 22 and adal ted to'be. raised or lowered thereby within t e casing 20. On the-false bottom 21 is removably mounted the retort or generating vessel 23 composed of refractry material, such fas glass -or porcelain. Above the generating vessel 23 is acollector 24, shown as removably supported on shelves 24E.' The collector 24 hasl a hop lerf-like bottom adapted to fit withinthe nec of the generating Areceptacle 23 .and `forni 'a tight joint-therewith, when the latter is raised to pipe 26,

its highest The collector 24 is preferably made of aluminium, but may be made of other suitable material which will notbe attacked by the generated gas. From'one end oi the collector 24 extends a main delivery pipe 25 which splits into two branches 25 ta ping the res ective mixing vessels 2 throng the top wals of the same, as clearly shown in Fig. 1 of the drawings. the branches 26 with the main pipe 25 4is located a weighted valve 27 for directing the gas into either oi' the vessels 2 and cutting the same o trom-the other, whenever so desired.

An aluminiumtube 28 is adjustably suspended within the generator. As shown, the tube 28 is suspended tromthe top wail of the collector 24 by means of nuts 29 having screw threaded engagement with the upper or screw threaded portion of the tube 28. The tube 28 is closed at its oppositeends but is perforated in the part thereof which works within the generating vesselhQS and the collector 24. The tube 28 isladapted to support a generating rod 30 of alvanized iron,

in such a way that the rod w1 l automatically.

feed down, by gravity, as the lower end ofthe rod is consumed in the gas generating action.

In the receptacle 23 is placed a solution com- 'posed of two-third parts nitric acid and onethirdpart vwater. Into this solution 'is placed sulfate ci copper tothe amount of about three per cent. of the liquid solution.

` Then, when the rod .30 of galvanized iron is at its lower end,

submerged in this solution, the generating action will take lace and the gas will accumulate in the co ector 24 and will pass out and 26 into the mixing chambers 2,' or one thereof, according to the way in which the valve 27 is set. The compounds of nitrogen and oxygen roduced from the materials indicated, are eavier than the air, and hence,

the gas will feed by gravity from the pipes 25 and 26 into the mixing chambers 2 and pass down through the latter. The gas supply to the respective' mixing chambers 2, tap the heads of' these chambers, at a point above the flour distributing head 14. 'Under the rotary motion of the distributer 14, the flour falling thereon, through the sleeve 18, will be thrown ofi from the distributer in the form of a shower, or in aiinely divided condition, well adapting the gas, entering through the pipe 26, to get directly at all theditferent particles of the flour. The gas generated from the ingredients above noted is nitric oxid (NO) and, in view of the way in which the generator gets its delivery to the mixing vessels 2, the gas can be delivered into the said mixing chambers in its substantially generated form, t. e. nitric oxid. The flour supply chute sections lxand 16 are always loaded full vof iour, and the outlet from the hopper bottom, under the action of position by the hand screw 22.

At the junction of therefrom through the'pip'es .25

the screw propeller 13, will be loaded full ci flour, the feed being ad properly to secure this result. lt follows that the iiour will enter the mixing chambers 2 and pass therethrough with very little (it any) air 7@ entering therewith. Hence, it will further Jfollow that the gas will remain and be applied to the flour in the 'form oinitric oxid or as it was generated at the generator.

Tests and analyses', made by an expert 75 chemist, have demonstrated that the` nitric oxid is a most eiicient form oi' bleaching agent. lt is found that, with an apparatus such as herein disclosed, adapted to utilize nitric oxid as the chief bleaching agent, the s@ bleaching talres place in much less time, or put another way, with much less gas per unit oi iiour than can be otherwise secured. The collector 24 is,` however, providedxat a point most remote from its outlet or delivery g5 pipe 25, with a buttery valve 31 which, if desired, can be set in its open position and thereby allowed to admit air to the collector 24, under the suction or outward movement of the generated into the delivery pi e 25. li suiiicient air is thus admitted througi the valve 31 into the collecting chamber 24 oi the generato?, the nitric oxid will taire on an additional atom of oxygen and become peroxid of nitrogen (HG2). The bleaching qualities of peroxid of nitrogen are well lrnown. Uur apparatus, however, is designed primarily' to supply and do the work with nitric oxid, although capable of affording the necessary air to get peroxid oi nitrogen, if that should be delo@ sired. So far as we know, we are the ii-rst to provide any apparatus capable of generating and applying nitric oxid to iiour or other grain products, for -bleaching and aging purposes.

All bleaching and aging apparatus disclosed or, in the prior art, so iar as known to us, delivers tothe flour peroxid of nitrogen or peroxid oi nitrogen cominingled with more or less per. oxid of hydrogen, or ozone with peroxid of hydrogen. None of these prior uses are siinilar to ours. le are the iirst, so i'ar as we know, to treat flour, or other grain roducts, with nitric oxid. lt should be no'te that the flour and the gas are both su plied to the mixing vessels solely under t ie action .oi 11s gravity', fand that the mixing vessels are suhs tantially air ti ht. lt will, oi course, be understood that t e structure of the apparatus may vary to a considerable extent, lwithout departing from the spirit oi our invention. l 12o lWhile especially designed Jfor bleaching and aging flour, it must be understood that the invention is-applicable to bleach and 'age other grain products, when in a ilinely divided or comminuted condition, and, in the claims, 125 the word iiourzz is `used in its broad or generic sense to over any and all kinds of grain products in a finely divided condition.

The novel process oi bleaching iiour and I other grain products, which?consistsinsub- 13o in disclosed, is not herein claimed, but is disl closed and claimedin another application filed as a division of this case. The gas enerator herein disclosed contains novel eatures constituting patentable invention not herein claimed, but which is claimed a divisional application [filed of even date with this amendment.

What we claim is 1. Thecombination of a nitric oxid generator and an inclosed flour and gas mixer admittin only the gas and i'lour.

2.. T e combination of a nitric oxid generator and an inclosed flour and gas mixer, re-

ceiving .the gas by gravity, and having a feed entrance and exit adapted, when in use, to become'packed with flour.

3. The combination of a nitric oxid generator, an inclosed mixing chamber receiving the 20 gas by gravity, and having feed entrance and exit adapted, when in use, to becomepacked with flour, and a distributer for scattering the flour throughthe gas chamber.

In testimony whereof we affix our signa-` 25 tures in presence of two Witnesses.

lFRED MEARS. s JOSEPH CRAIG. 

